1. FIELD OF THE INVENTION
The present invention relates to an improvement to a safety pin, the improvement being specifically that the coils of the torsion spring are spaced apart so as not to entrap fabric threads therein.
2. DESCRIPTION OF THE PRIOR ART
The problem of a safety pin pinching threads of a fabric in the torsion spring has long been recognized in the prior art. U.S. Pat. No. 1,170,508, issued to James H. Boye on Feb. 8, 1916; U.S. Pat. No. 1,501,627, issued to Nathaniel L. Silverman on Jul. 15, 1924; and U.S. Pat. No. 1,623,532, issued to Andrew Dudas et al. on Apr. 5, 1927 all disclose structure provided to prevent pinching of fabric in a safety pin. Boys bends the straight sections of the pin as they extend from the spring coils, forming concavities which ward off fabric that might otherwise be pinched in a crevice that would ordinarily be defined between one straight section and a coil. Silverman provides a stop formed by a band, recited in the specification but not illustrated, which prevents fabric from advancing into such intimate relation therewith so as to become enmeshed with the coil. Dudas forms a bend in the coil serving as a stop, which bend is clearly illustrated in the drawings.
U.S. Pat. No. 1,174,485, issued to Mason B. Franklin on Mar. 7, 1916, discloses a pin having a conventional coil spring. The spring is illustrated as being axially extended, but no further details are provided in the discussion of the invention. An open receptacle for holding the pointed end is formed by bending the wire at the other end of the pin, and this open receptacle has great width compared to the ordinarily employed, U-shaped head or sheath. The open coil spaces apart straight segments of wire to enable the sharp member of the pin to be centered in the receptacle. The issue of pinching the fabric being retained is not addressed by Franklin.
U.S. Pat. No. 1,141,952, issued to Chelcias E. Faulks on Jun. 8, 1915, discloses a pin which separates two pieces of cloth so that one may be released while maintaining attachment to the second. This is accomplished by a stop formed by a bend in the pin.
None of the above inventions and patents, taken either singly or in combination, is seen to describe the instant invention as claimed.